JP2003322313A - Oxygen burner for arc furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a burner device having improved burner efficiency by enabling burner combustion in an arc furnace, which dissolves a metal material, at the beginning of dissolution and achieving safe burner combustion by enabling sure combustion of a fuel even for use in a preheating furnace. <P>SOLUTION: The oxygen burner is provided outward from the furnace wall of the arc furnace which dissolves the metal material, for injecting combustion flames of the fuel burnt together with oxygen inward to the furnace wall to accelerate the heat and/or dissolution of the metal material. It comprises a first fuel blowing pipe for blowing a first fuel from a central portion of the oxygen burner, a first oxygen blowing pipe for blowing first oxygen from the outer periphery of the first fuel blowing pipe, a second fuel blowing pipe for blowing a second fuel from the outer periphery of the oxygen blowing pipe, and a second oxygen blowing pipe for blowing second oxygen from the outer periphery of the second fuel blowing pipe. An insertion hole is formed by an opening hole provided in a panel of the arc furnace and a mounted seat mounted on the outer face of the panel, and the burner is mounted at its end into the insertion hole. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to the melting of metallic materials,
The present invention relates to an oxygen burner provided on a furnace wall of an arc furnace used for refining molten metal.

[0002]

2. Description of the Related Art In recent years, in an arc furnace for melting metal materials such as scraps, in order to reduce not only electric melting but also electric power cost, the power supply equipment of the arc furnace is reduced to 1
The base has two furnaces for charging metal materials, one side melts with electricity, and the other furnace attaches to the exhaust gas discharged from the melting side furnace or the lid installed at the top of the furnace. An arc furnace of one power source and two furnace type in which a metal material is preheated by the burner is put into practical use, and various burners attached to the furnace wall are used in order to further reduce the electric power cost.

As a burner for preheating and heating a metal material charged in a furnace on the preheating side by a burner attached to the furnace wall, Japanese Patent Laid-Open No. 59-202388 discloses a burner body having a combustion tip. In addition to the seal bar, the burner device inserts the burner tip into the burner insertion hole of the furnace wall during the combustion time period, and the burner chip is pulled out from the burner insertion hole during the combustion stop time period, and the seal bar is inserted instead. It is disclosed. According to this burner device,
When the burner tip is pulled out from the burner insertion hole, it is possible to start combustion outside by installing an auxiliary burner outside the furnace wall.

Further, in Japanese Unexamined Patent Publication No. 10-9524, an oxygen ejection pipe for ejecting oxygen gas from a central portion, a fuel ejection pipe for ejecting fuel from an outer peripheral portion of the ejection pipe, and an outer periphery of the fuel ejection pipe are disclosed. An annular space formed by a triple tube of combustion oxygen gas ejection pipes for ejecting combustion oxygen gas from the section, a narrowed portion is provided at the tip of the oxygen gas ejection pipe, and the fuel ejection pipe and the combustion oxygen ejection pipe are formed. There is disclosed a burner device in which a swirl vane is provided. Furthermore, JP-A-2000-171158
The publication discloses a burner main body which is provided outside a furnace wall of a metal melting furnace and ejects a combustion flame from a tip portion toward the inside of the furnace wall, and a cylindrical body which extends substantially along the combustion flame injection direction. Has a shape, the base side surrounds at least the tip of the burner body,
A ratio R of the length b of the combustion flame to the length a from the tip of the burner body to the tip side of the combustion cylinder, the combustion tube having a tip inserted into an insertion hole formed in the furnace wall of the melting furnace. (= B
A burner device is disclosed in which / a) is selected in the range of 0.2 ≦ R ≦ 2.0.

[0005]

However, as described above, since the various burner devices of the prior art do not have an ignition heat source for burning fuel at the burner tip,
On the melting furnace side where electricity is melting, it can be used after the middle stage of melting when arc sparks fly, but at the initial stage of melting when the raw material is charged into the arc furnace, scraps etc. When the metallic material is present, there is a problem that the ratio of contributing to the promotion of dissolution of the metallic material is reduced only by ejecting the fuel without burning.

Further, in the case of using a burner on the preheating furnace side in an arc furnace of the one power source and two furnace type, although there is an exhaust heat gas on the upper surface of the scrap or an ignition heat source by the burner installed on the furnace lid, scrap Since there is no heat source in the part below the middle layer, the fuel does not burn but is only ejected into the melting furnace. Especially, in the case of gas fuel,
Unburned gas fills the furnace and there is a risk of sudden explosion. Therefore, when the burner is used also on the preheating furnace side, it is necessary to always burn it on the melting furnace side even after the completion of melting.
Normally, about 200-400m3 when used in a melting furnace
Since the fuel of (Normal) / Hr is burned, even if the combustion amount is reduced, it is about 1/10, which is 20 to 40 m3 (Normal).
mal) / Hr must be burned, and the economy is very poor. Furthermore, when a metallic material is charged into the furnace while being burned, the combustion flame is blown out due to the impact and gust of the charging because the discharge rate of the combustion flame is low due to the reduction of the combustion amount. There was a problem that there is a high possibility.

Further, in a burner device capable of extracting the burner tip out of the furnace and igniting it with an auxiliary burner outside, flame leaks from a gap between the insertion hole and the outer peripheral portion of the burner tip, and a hose, a cable, etc. around the burner. Is highly likely to burn out. In addition, maintenance cost increases due to the complicated structure. Further, in a burner having a burner body and a combustion cylinder, since high-temperature combustion flame exists even when the burner combustion flame is maintained in the burner insertion hole, the temperature inside the combustion cylinder becomes high and the combustion flame is long. In addition, there is a risk that the combustion flame will contact the inside of the combustion cylinder and be damaged, and if the combustion cylinder has a water-cooled structure to extend the life, there is a high risk of damage to the structure and water leakage due to the combustion flame. There was a problem. Therefore, the present invention solves the problems of the prior art as described above, burner combustion can be performed from the initial stage of melting in an arc furnace for melting a metal material, and the burner efficiency is improved. An object of the present invention is to provide a burner device capable of safely burning a burner by burning fuel to a burner.

[0008]

The present invention has been made as a result of intensive studies for solving the above-mentioned problems, and the gist thereof is the following contents as set forth in the claims. . (1) Providing a combustion flame, which is provided outside a furnace wall of an arc furnace that melts a metal material and burns a fuel together with oxygen, toward the inside of the furnace wall to promote heating and / or melting of the metal material In the oxygen burner, the first fuel injection pipe (3) for injecting the first fuel from the central portion of the oxygen burner.
1) and from the outer peripheral portion of the first fuel injection pipe (31) to the first
A first oxygen ejection pipe (32) for ejecting oxygen gas of
A second fuel ejection pipe (33) for ejecting a second fuel from the outer peripheral portion of the oxygen ejection pipe (32) and a second oxygen gas ejected from the outer peripheral portion of the second fuel ejection pipe (33) Second
And a mounting seat (13) attached to the outer surface of the panel, and an opening provided in the panel (10) of the arc furnace and an insertion hole (12). , The tip portion (11) of the burner through the insertion hole (1
An oxygen burner for an arc furnace, which is attached to 2).

(2) The angle of the ejection hole (44) for ejecting the second oxygen gas is set within a range of 3 to 10 degrees with respect to the axis of the oxygen burner. Oxygen burner. (3) The fuel is burned with air so that the tip of the combustion flame enters the insertion hole (12) between the end of the furnace inner surface of the panel (10) and the tip of the oxygen burner (11). An auxiliary burner attached to the auxiliary burner, and a removable shield plate (5) at the rear end of the fuel injection pipe (54) of the auxiliary burner.
8) by attaching the fuel injection pipe (54)
The oxygen burner according to (1) or (2), wherein the penetrating bar can be inserted from the rear end of the oxygen burner.

According to the present invention, in the first smelting furnace at the start of operation, the melting of the metal material progresses to some extent and the time when ignition by an arc is possible, similar to the normal ignition method of an oxygen burner. If the first fuel and the first fuel-combusting oxygen gas are ejected, they are ignited by an arc. Whether the first fuel is reliably burning can be detected by a flame detector attached to the rear end of the burner. Therefore, since the heat source always exists at the tip of the burner, it is possible to ignite the main second fuel regardless of the state of the melting furnace, and burner combustion from the next melting furnace from the beginning of melting. The burner efficiency is improved, and the burner combustion can be reliably started on the preheating furnace side. If a misfire phenomenon is detected during use in the preheating furnace, it may be burned again when the preheating furnace moves to the melting furnace.

[0011]

1 is a sectional view showing a simplified structure of an oxygen burner 1 of an arc furnace which is an embodiment of the present invention, and FIG. 2 shows the oxygen burner 1 shown in FIG. FIG. 4 is a front cross-sectional view showing a simplified configuration of an arc furnace provided, and FIG. 3 is a front cross-sectional view showing a simplified configuration of an arc furnace of one power source and two furnaces provided with the oxygen burner shown in FIG. 1.
5 is a cross-sectional view showing a simplified internal structure of the tip portion of the oxygen burner 1 shown in FIG. 1, FIG. 5 is a front view of the end surface of the oxygen burner seen from the front, and FIG. It is a front sectional view which simplifies and shows the composition which attached the auxiliary burner in the oxygen burner. FIG. 7 shows the auxiliary burner 2 shown in FIG.
It is a front sectional view which simplifies and shows the composition of 0. Figure 8
It is the figure which inserted the penetration bar into the fuel injection hole of the auxiliary burner.

The oxygen burner 1 in an arc furnace for melting a metal material is mainly installed outside the furnace wall of the arc furnace and burns fuel with oxygen to accelerate heating or melting of the metal material. The arc furnace of FIG. 2 is a three-phase alternating current arc type melting furnace for melting a metal material, and includes a furnace body 3 and a furnace lid 4.
And three electrodes 5 (only two are shown in this figure). The furnace main body 3 is a bottomed cylindrical container having an opening at the top, and has a furnace wall 6 and a furnace bottom 7. The furnace wall 6 is provided with an iron shell 8 forming an outer furnace shell, and a refractory brick 9 or a panel 10 (in this embodiment, a water-cooled panel 10 is shown) lined on the inner peripheral surface of the iron shell 8. There is. The furnace bottom 7 is provided with an iron shell 8 forming an outer furnace shell, and an inner peripheral surface of the iron shell 8 provided with a refractory brick 9 lined to hold a high temperature molten metal in which a metal material is melted. .

FIG. 3 shows a DC arc furnace of one power source and two furnace type having one power supply facility and two furnace bodies for charging metal materials. In this equipment, two arc furnaces having a furnace body 3, a furnace lid 4, an electrode 5, a furnace bottom 7 on a furnace bottom 7 are installed, and one of the arc furnaces (tentatively named furnace A in this figure) is used as an electrode. 5 while the arc is being struck between the furnace bottom electrode 20 and the metal material to melt the metal material, the other furnace (tentative name B furnace in this figure) uses the exhaust gas from the furnace A to discharge the metal material. Preheat. The exhaust gas passes through the elbow duct 21 on the furnace lid 4 of the A furnace, the connecting duct 22, the elbow duct 21 on the furnace lid 4 of the B furnace, the metal material, the moving duct 23 along the arrow in the figure, and finally to the dust collector. To collect dust. Since the moving duct is unnecessary in the melting furnace, it moves and closes the opening with the lid 24.

In FIG. 1, the water-cooled panel 10 provided on the inner peripheral surface of the furnace wall 6 has an insertion hole 12 into which the tip portion 11 of the oxygen burner 1 is inserted. Iron shell 8
A mounting seat 13 for fixing the oxygen burner 1 to the iron skin 8 is provided on the outer periphery of the. The end surface 14 of the tip portion 11 of the oxygen burner 1 is set on the axis of the insertion hole 12 such that the distance between the end surface 14 and the furnace inner surface 15 of the panel 10 is 1 to 2 times the diameter of the burner insertion hole 12. Is desirable.

The oxygen burner 1 is composed of a hexagonal tube as shown in the sectional view of FIG. A first fuel jet pipe 31 for jetting a first fuel from a central portion, a first oxygen gas jet pipe 32 for jetting a first oxygen gas from an outer peripheral portion of the first fuel jet pipe 31, and A second fuel ejection pipe 33 for ejecting the second fuel from the outer peripheral portion of the first oxygen gas ejection pipe 32.
And a second oxygen jet pipe 34 for jetting a second oxygen gas from the outer peripheral portion of the second fuel jet pipe 33, and the oxygen burner 1
The tip 11 of the is preferably water-cooled in order to protect it from radiant heat from a high-temperature furnace and radiant heat from a high-temperature flame due to oxygen combustion, and is used to flow cooling water to the outer peripheral portion of the second oxygen ejection pipe 34. It is composed of a partition pipe 35 and an outermost peripheral pipe 36. The outermost peripheral pipe 36 is provided with a mounting seat 37 for mounting it on the mounting seat 13 of the iron skin 8, and has a structure that can be attached and detached for maintenance. further,
The first oxygen jet pipe 32, the second fuel jet pipe 33, the second oxygen jet pipe 34, and the outermost peripheral pipe 36 are the oxygen burner 1
Is integrally connected to the block 38 at the tip of the.

FIG. 5 shows a state in which the end surface 14 of the oxygen burner 1 is viewed from the front, and the first fuel jetting the first fuel to the center portion.
No. 1 fuel ejection hole 41, one first oxygen ejection hole 42 for ejecting the first oxygen gas on the outer circumference thereof, and a second fuel ejection hole 43 for ejecting the second fuel on the outer circumference thereof. And a few
Further, several second oxygen ejection holes 44 for ejecting the second oxygen gas are provided on the outer circumference thereof. It should be noted that the ejection holes 43 and the ejection holes 44 may each be one in which a multi-tube is extended to the end surface of the burner, but in particular, in the cross-sectional view of FIG. 4, the ejection holes for ejecting the second oxygen gas are ejected. The holes 44 are provided with an inclination of α with respect to the axis of the oxygen burner 1, and normally α is preferably provided in the range of 3 to 10 degrees. Therefore, the ejection holes 44 for ejecting the second oxygen gas
Must have a tilt angle of α with respect to the axis,
Several holes are desirable for processing.

6 and 7 show an embodiment in which an auxiliary burner 50 is attached. A mounting seat 13a for fixing the auxiliary burner 50 is attached to the iron skin 8, and a cylindrical insertion hole 51 extending substantially along the injection direction of the combustion flame of the auxiliary burner 50 is provided inside the panel 10. However, one end side of the auxiliary burner body surrounds at least the tip portion of the auxiliary burner body, and the other tip side faces the outer peripheral surface of the insertion hole 12 for inserting the oxygen burner 1. End face 14 of tip 11 of oxygen burner 1
Is preferably located on the inner side of the furnace opposite to the point A on the outer peripheral surface where the insertion hole 51 intersects on the axis of the insertion hole 12. Further, the end surface 53 of the tip portion 52 of the auxiliary burner 50 is preferably located closer to the auxiliary burner than the point A on the outer peripheral surface where the insertion hole 12 intersects on the axis of the insertion hole 51. The auxiliary burner 50 has a fuel injection pipe 54 for ejecting fuel from the center.
And a double pipe of an air jet pipe 55 for jetting air for burning the fuel from the outer peripheral portion of the fuel jet pipe 54. The auxiliary burner 50 has a low radiant heat from the inside of the furnace and has a low flame temperature because it is burned by air, so that it is not necessary to cool the tip portion 52. Auxiliary burner 50
At the rear end, a spark plug 56 for first igniting and a flame detector 57 for detecting the presence or absence of combustion of fuel.
And a removable shield plate 58 is attached to the outermost end of the fuel injection pipe 54. The shield plate 58 is removed, and the penetrating bar 59 can be inserted into the fuel injection pipe 54. This is so that when a foreign substance from the inside of the furnace adheres to the panel insertion hole 12 part, the foreign substance 62 is scraped off by the penetrating bar 59.

The method of using the oxygen burner in the above configuration will be described below. In a melting furnace at the start of operation, a metal material is charged into the furnace and then melting is started by an arc. After that, if fuel (LPG is used in the present embodiment) is ejected from the first fuel ejection pipe 31 of the oxygen burner 1 and oxygen is ejected from the first oxygen ejection pipe 32, it is easily ignited by an arc. Since the purpose of combustion of the first fuel is to serve as a spark for burning the second fuel, the ejection amount for burning may be about 1 to 3 m3 (Normal) / Hr.

In the state where the first fuel is burning, the second fuel
When the second fuel is ejected from the fuel ejection pipe 33 and the second oxygen is ejected from the second oxygen ejection pipe 34, the fuel is immediately burned. After burning the second fuel for the required time, stop the second fuel and the second oxygen, and switch to the air injection to prevent clogging of the injection hole to the oxygen burner end face due to splash from the furnace. . As a result of actually using the present oxygen burner 1 in a three-phase AC arc furnace having a nominal 60 tons, even if the raw material was charged in the state where the first fuel was burned, it was hardly blown out. This is due to the fact that a space is provided between the furnace inner end surface 15 and the oxygen burner 1 end surface 14 in the insertion hole 12 of the panel 10.

Further, by tilting the second oxygen gas ejection holes 44, the water-cooled panel 10 is operated with a certain amount of cooling water passing, and as a result, 100% of the second fuel is supplied.
When m3 (Normal) / Hr was burned, the difference between the inlet temperature and the outlet temperature of the cooling water was 15 ° C, but when the second fuel was burned at 200 m3 (Normal) / Hr,
Since the temperature difference of the cooling water is lowered to 12 ° C., the combustion amount can be increased without the combustion flame coming into contact with the inner surface of the insertion hole 12 of the oxygen burner 1. The inclination angle is preferably 3 to 10 degrees. If the inclination angle is 3 degrees or less, the combustion flame may come into contact with the insertion hole, and if the inclination angle is 10 degrees or more, the fuel and oxygen gas are not uniformly mixed and the flame persistence is improved. This is because it will be lower.

Although this arc furnace was operated continuously for 24 hours, the flame detector 16 detected misfire about 2 to 3 times / month, but in order to surely ignite it immediately at this time as well. When the auxiliary burner 50 was attached, the first fuel of the oxygen burner 1 could be burned easily and reliably by igniting the auxiliary burner at the same time as detecting the misfire. After burning the first fuel, the auxiliary burner is economical to stop the combustion of the auxiliary burner and switch to jetting only air to prevent clogging of the tip.

Further, since the flame detector 57 detected misfire, the first combustion state of the oxygen burner was confirmed and the combustion state was sometimes maintained. The cause was investigated, and the auxiliary burner of FIG. 6 was found. In the mounting diagram of 50, since the insertion hole 51 for attaching the auxiliary burner 50 has a slope that rises to the right, a lump of slag or splash exists in the space portion of the insertion hole that exists above the end surface 53 of the auxiliary burner 50 to the right. Was found to have accumulated and blocked the field of view of the flame detector 57. Although it is possible for an operator to enter the furnace to remove lumps of slag or splash after cooling the inside of the furnace, the shield plate 58 attached to the outermost end of the fuel injection pipe 54 of the auxiliary burner 50 is removed. It is possible to easily remove the slender bar by pushing it into the inside of the fuel injection pipe 54. In addition, in the 60 ton arc furnace, the auxiliary burner 50
Was attached to the lower part of the oxygen burner 1 so as to rise to the right, but the attachment position of the auxiliary burner 50 is not limited,
The effect is the same regardless of whether the oxygen burner 1 is attached vertically or horizontally. FIG. 8 is a view in which a penetrating bar is inserted into the fuel ejection hole of the auxiliary burner. In FIG. 8, a penetrating bar 59 is inserted into the fuel injection pipe 54 to insert the through hole 1 in the panel.
When foreign matter from inside the furnace adheres to the 2nd part, this penetration bar 5
The foreign matter 62 can be scraped off by means of 9.

[0023]

According to the present invention, burner combustion can be performed from the initial stage of melting in an arc furnace for melting metal materials to improve burner efficiency, and when used in a preheating furnace, the fuel is surely burned to ensure safety. An oxygen burner capable of performing burner combustion can be provided, and specifically, the following industrially useful remarkable effects are exhibited. 1) By installing the oxygen burner according to claim 1 in an arc furnace that heats and melts a metal material, burner combustion becomes possible from the initial stage of melting, and the melting time is shortened by improving the usage rate of burner combustion, and electric power consumption Can be reduced. 2) By installing the oxygen burner according to claim 1 in an arc furnace of one power source and two furnace type, burner combustion can be performed safely and reliably even on the preheating furnace side.

3) Further, by attaching the auxiliary burner, even if the burner combustion flame disappears, the combustion can be resumed immediately, so that the oxygen burner usage rate can be improved.
4) Even if the tip hole of the auxiliary burner is clogged, it is possible to easily remove the clogging from the outside by removing the shielding plate provided at the rear end of the burner and inserting the penetrating bar into the fuel injection pipe. The burner usage rate is further improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a simplified configuration of an oxygen burner 1 of an arc furnace which is an embodiment of the present invention.

FIG. 2 is a front sectional view showing a simplified configuration of an arc furnace including the oxygen burner 1 shown in FIG.

FIG. 3 is a front sectional view showing a simplified configuration of an arc furnace of a one power source and two furnace system equipped with the oxygen burner shown in FIG.

FIG. 4 is a sectional view showing a simplified internal configuration of the oxygen burner 1 shown in FIG.

FIG. 5 is a front view of the end surface of the oxygen burner 1 as seen from the front.

6 is a front cross-sectional view showing a simplified configuration of the oxygen burner of FIG. 1 with an auxiliary burner attached.

FIG. 7 is a front sectional view showing a simplified configuration of the auxiliary burner 50 shown in FIG.

FIG. 8 is a view in which a penetrating bar is inserted into a fuel injection hole of an auxiliary burner.

[Explanation of symbols]

1: Oxygen burner, 3: Furnace body, 4: Furnace lid, 5: Electrode,
6: Furnace wall, 7: Furnace bottom, 8: Iron crust, 9: Fire brick, 10:
Panel, 11: tip part, 12: insertion hole, 13: mounting seat, 14: oxygen burner end surface, 15: panel furnace inner surface, 1
6: Flame detector, 20: Furnace bottom electrode, 21: Elbow duct,
22: connecting duct, 23: moving duct, 24: lid, 3
1: 1st fuel ejection pipe, 32: 1st oxygen ejection pipe, 3
3: Second fuel jet pipe, 34: Second oxygen jet pipe, 3
5: Partition pipe, 36: Outermost pipe, 37: Mounting seat, 3
8: block, 41: first fuel ejection hole, 42: first oxygen ejection hole, 43: second fuel ejection hole, 44: second oxygen ejection hole, 50: auxiliary burner, 51: insertion hole, 52: tip part of auxiliary burner, 53: end surface of auxiliary burner, 54:
Fuel jet pipe for auxiliary burner, 55: Air jet pipe for auxiliary burner, 56: Spark plug, 57: Flame detector, 58:
Shielding plate, 59: through bar, 60: air supply port for auxiliary burner, 61: fuel supply port for auxiliary burner, 62: foreign matter

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ken Kanekawa             3434 Shimada, Hikari-shi, Nippon Steel Works             Inside the Shoko Ironworks (72) Inventor Hirofumi Nakane             3434 Shimada, Hikari-shi, Nippon Steel Works             Inside the Shoko Ironworks (72) Inventor Kokubun Seiei             20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel shares             Company Technology Development Division (72) Inventor Tsutoshi Maeda             2-4-7 Kyomachibori, Nishi-ku, Osaka-shi, Osaka             Chugai Furnace Industry Co., Ltd. F term (reference) 3K017 CA03 CA04 CA09 CB08 CB11                       CC08 CD04 CE05 CH04                 3K019 AA02 BA01 BB05 BD01 BD11                       BD12 CC02                 3K023 JA03                 4K045 AA04 BA01 GB02 GB08

Claims (3)

[Claims] 1. A heating and / or melting of a metal material is provided outside a furnace wall of an arc furnace for melting a metal material, and a combustion flame produced by burning a fuel with oxygen is injected into the furnace wall to inject the metal material. In the oxygen burner for accelerating the combustion, a first fuel jet pipe (31) for jetting a first fuel from the central portion of the oxygen burner, and a first oxygen jet from the outer peripheral portion of the first fuel jet pipe (31). A first oxygen jet pipe (32) for jetting gas, a second fuel jet pipe (33) for jetting second fuel from the outer peripheral portion of the oxygen jet pipe (32), and the second fuel jet pipe A second oxygen ejection pipe (34) for ejecting a second oxygen gas from the outer peripheral portion of the pipe (33), and an opening provided in the panel (10) of the arc furnace and an outer surface of the panel. While forming the insertion hole (12) with the attached mounting seat (13), An oxygen burner for an arc furnace, wherein a tip portion (11) of the burner is attached to the insertion hole (12). 2. The angle of the ejection hole (44) for ejecting the second oxygen gas is 3 to the axis of the oxygen burner.
The oxygen burner according to claim 1, wherein the oxygen burner has a range of 10 degrees. 3. The fuel is burned with air, and the tip of the combustion flame is inserted into an insertion hole (12) between the end of the inner surface of the furnace of the panel (10) and the tip (11) of the oxygen burner. A trailing end of the fuel jet tube (54) having an auxiliary burner mounted so as to enter, and by attaching a removable shield plate (58) to the trailing end of the fuel jet tube (54) of the auxiliary burner. The oxygen burner according to claim 1 or 2, wherein the through-bar can be inserted from the inside.